Legal act is matter for discussion involving political party (8)
I believe the answer is:
issuance
'legal act' is the definition.
'matter for discussion involving political party' is the wordplay.
'matter for discussion' becomes 'issue' (I've seen this before).
'involving' indicates putting letters inside.
'political party' becomes 'ANC' (African National Congress, South African party).
'issue' placed around 'anc' is 'ISSUANCE'.
'is' acts as a link.
(Other definitions for issuance that I've seen before include "promulgation" , "Act of sending out" , "publication" .)